System Id; System Information Table - Compaq EN Series Technical Reference Manual

Chapter 8 BIOS ROM
8.4.1

SYSTEM ID

The INT 15, AX=E800h BIOS function can be used to identify the system board. This function
will return the system ID in the BX register.
System Board
007998 or 008123
8.4.2

SYSTEM INFORMATION TABLE

The System Information Table (SIT) is a comprehensive list of fixed configuration information
arranged into records. The INT 15 AX=E807h BIOS function accesses the SIT by returning a
pointer in ES:BX to indicate the location of the SIT. This section lists the default values that
should be read from the SIT. For specific bit descriptions and more detailed information on the
SIT refer to the Compaq Basic Input/Output System (BIOS) Technical Reference Guide.
Power Conservation Record, SIT Record 01h
Byte Function
00h Record ID
01h No. of Data Bytes in Record
02h Volume, CPU Speed, Screensave, PWR Consv. Mode
03h LED Blink, Popup, APM, PC Level, MAXBRIGHT Control
04h SW Power Cntrl., Screensave/Hard Drive Timeouts, PWR
05h Magic Packet Flag, SMI, Modem Installed
06h-0Bh Popup Location
0Ch Quick Engy. Save, Magic Packet PWR, Suspend, CPU Sp.
NOTES:
[1] Will be determined at runtime
[2] Unsupported function - read all 0s.
Timeout Counter Record (System Standby), SIT Record 02h
Byte Function
00h Record ID for System Standby Timeout
01h No. of Data Bytes in Record
02h First Value
03h
04h
05h
06h
07h
08h
09h
0Ah Last Value
8-6 Compaq Deskpro EN Series of Personal Computers
Desktop and Minitower Form Factors
CMOS ID ROM Type
7Eh 686T3
Third Edition - September 1998
System ID
0400h
Default
Value
01h
0Bh
07h
C4h
90h
[1]
[2]
39h
Default
Value
02h
09h
0
10
15
20
30
60
120
180
240